Train control



F. E, CARTER TRAIN CONTROL Dec. 27, 19.27.

2 Sheet$-$heet 1 Original Filed NOV. 21, 1923 S m EH 3 m. fi m m 6 P N. M 1 Lfim h v n. N\ M m I In J H W on A m H W N m o w W n W 2 1 llllllll llllllllllllllllllllll l I [Trill] 8 om c a Dec. 27, 1927. 1, 54,4 1

P. E. CARTER TRAIN CONTROL Original Filed Nov. 21, 1923 2 Sheets-Sheet 2 ENTOR.

6 M? z m ,ATORNEY- id er. 27, 12927.

srA'rss PATENT OFFICE.

PAUL E. CARTER, F BBGNXVILLE, NEW YORK, ASSIGNOR T0 GENERAL RAILWAY SIGNAL OOIVIIEANY, 0F RQCHESTER, YORK. I

TRAIN conrno Application filed November 21, 1923, Serial No. 676,109. Renewed May 28, 1927.

This invention relates'to automatic train control systems, and more particularly to those types of systems in which a variable permissive speed may be set up at successive pointsalong the track under caution traffic conditions.

In the provision of means to allow a train to proceed at a speed which will assure stoppage of the train before reaching the end er a block when the nextbloclr in advance is occupied, and which at the same time, will iot restrict the speed unnecessarily,it has been found expedient to employ a device driven from the wheels of the railwa vehicle which is gradually restricts the permissive speed the vice has been initiated.

device initiated at the entrance to a block,

is employed, this being especially true of long blocks.

With the above and other considerations in mind it is proposed to provide a car-carried system having two cams, the first of which, conveniently called the high cam, is adapted to restrict the speed gradually from a high to a medium value'and the second cam conveniently called the low cam, is

1 adapted to restrict the speed from a medium to low value, and to provide means for initiatingsuch cams by influences transmitted from the trackway to the vehicle through an intervening air gap when a t'ain passes through a caution block, the high cam being shaped so that the permissive speed is gradually brought down to a constant me dium speed limit which is enforced for a ct nsiderable distance; and the low cam beshaped to restrict the speed'i'rom said medium value to continuing speed of lower value; to provide means for restoring the high cam when it has reached its ultimate position and to provide means for restoring both the low and the high cams when the ow cam has reached its ultimate position;

the influence communication means provided being such that if an impulse is received when both cams are in their restored position only the high cam is initiated and if an impulse is received and the high cam has already started to operate the low cam. is initiated; and to provide trackway apparatus which transmits a single impulse to the carcarried apparatus near the entranceto a caution block and transmits two successive impulses at that point in a block where the, low cam should be initiated providing caution tratiic conditions of the particular block exist; so that, if the high ca-m has not al ready been initiated, possibly because the block has changed from a clear to a caution block in the meantime or because it has already been restored, the two successive imoulses will start both the high andthe low cam.

Other objects, purposes and characteristic features of the invention will appear as the.

- view of the speed restricting apparatus forming a part oi the present invention; and

Fig. 3 is a diagrammatic vlew of the car- .carried apparatus in which some of the devices have been shown conventionally.

Traclcway apparatus.

Referring particularly to Fig. l ot the drawings, there has been illustrated the usual "form of traclrway comprising rails 1 divided by insulating joints 2 into blocks in the usual manner, the block I and the adjacent ends of two other blocks H and J being shown. Since the various blocks are the same like parts of each blockhave been assigned like reference characters with distinctive exponents. Each of the blocks is providedwith the usual track battery 3, or other suitable source of energy, and with the usual track relay i. The particular train control system illustrated is preferably used in connection with systems employing a wayside signal and although a color light signal, or a position light signal may be used a semaphore signal Z has for convenience been shown conventionally wi 'hout illustrating its well-known circuits and control devices.

Near the entrance to each. block is pro-- vi-ded a track element T comprising a mag- V netizable core of general U'shape terniinating in enlarged pole pieces 6 disposed a suitable distance (about two inches) above the level of the track rails and on the outside thereof. Qn the baclr yoke of the core 5, which is n'eferably laminated, is provided a coil 7 of usual and, well-known construction..- This coil. under clear tra'liic conditions ahead is closed in a circuit of low resjsistance by the front contact 8 of the line relay 9, the line relay- Sl being maintained energized under clear trailic conditions ahead through the front contact 10 of the track relay t by a suitable source of energy one terminal of which has been designated 13 the other terminal being connected to a connnon return wire C. At a point suitably distant in the block is provided another line relay 11 connected in multiple with the line relay 9 and adapted to maintain the coil '5 and 7 of the track elements T and T" in a circuit of low resistance by reason of its front contacts 12 and 13 which are closed when the block ahead is unoccupied.

dust above the track apparatus shown in Fig. 1 has been graphically illustrated the permissive speeds enforced by the train control system shown and more clearly de' scribed hereinafter. i v hen a train is pass ing through a caution block the solid line .ldillustrates the permissive speed enforced.

by the high cam and the dot-and-dash line 17 graphically shows the permissive speed enforced by the low cam.

Car-carried apparatus.

Speed restricting devices-Referring more particularly to rig. 2 there has been shown on the railway vehicle a governor shaft 20 which is driven by the wheels and axle of the vehicle in any suitable manner (not shown). On this shaft 20 is provided a speed responsive device (i of the welllrnown centrifugal type including a grooved collar 21 urged upwardly by the conipression spring 22 and 21C apted to be moved downwardly by reason of centrifugal force acting on the weights 23 in response to the rotation of shaft 20. "his governor G is preferably supported in a spring mounted mechanism casing, in which is journaled a speed shaft 2 having a bifurcatedarin engaging opposite sides of the grooved collar 21, so that the speed shaft and the speed. arm 25 fastened thereto, inove about the axis of this shaft in proportion to the speed ot the train. On the governor shaft 20 is provided a worm 27 which through suitable gears 28, 29 and 30 is adapted to. rotate the pnnen 31. This pinion 31 is piv-' normally attracted by the core 35 magnetized by the current flowing in the coil 36, thereby holding this armature 34 in its lower position and maintaining the pinion3l out ot n'iesh with tl e gee 38 secured to the cam shaft 89. The gear 38 is provided with a mutilated portion 38 so that ,when the pinion 31 is in mesh with the gear 38 it may be initiated and turned only to a point where the pinion 31 reaches the mutilated portion.

To the cam shaft 39 is pinned a pinion 4L1 operativelyengaging a gear sect-M42 which is biased to an intermediate position by two compression coil springs 43' engaging this gear sector and suitable projecting lugsist, so that the gear normally maintained in a position to have the mutilated portion directly opposite the pinion 31. To the cam shaft 39 is secured a'cain 46. Near the cam 46 is provided a sect-or 47 biased in a counter clockwise direction bya spring 48; In order to cause the sector 47 to respond to the joint action of the. speed arm '25 and the ca1n46 the free end of the speed arm 25 is pivotally secured to a floating lever 49 having a roller 50 journaled-to its free end which engages the surface of the cam 4L6. A link 51 has one of its ends pivotally secured to an eccentrically located pin 52 projecting from the sector 4-7, so that either a rotation of the speed sha ft2 i due to increase in speed or a rotation of the earn shaft 39 due to progress of the vehicle causes inoveinent of the sector 47 In other words, the sector l! responds jointly to the speed of the vehicle as determined by the speed governor V G through the speed shaft 2% and the restriction of the train withrespect to the point at which the can) 16 is initiated as manifested by the cam 46 acting through gears connected tothe wheels of the vehicle.

Adjacent to the sector at? is'provided an insulating block 5st to which are secured the ill) that excessive speed of the vehicle as compared with the permissive speed set up by the cam 46 causes an automatic brake application. v

(Hirer oar-carried Zeoicc.s=.0n the railway vehicle are located a number of devices which are connected together to constitute the car-carried systems, one of these devices comprises a suitable influence coi'i'm'mnicating car element L, which consists of a core 62 preferably laminated and of eneral inverted U-shape terminating in enlarged pole pieces 63 and mounted on the vehicle so that the core 62 is adapted to inductively cooperate with the core ofthe track elements T,"T and T and'thereby receive impulses from such. track elements. 011 the legs of the core 62 are provided a primary coil P and a secondary coil S, respectively.

The car-carried apparatus also includes a control relay GR and a repeater relay RR, these relays are preferably 01 the tractive armature type in which the armature is pivotally secured about a vertical axis in a manner so that this axis passes through the center of gravity of the arn'iature thereby causing the armature to be balanced and not subject to jars or vibrations. These rela s are preferably mountedin a heavy casing which is spring supported, so as to protect them from jars and vibrations as well from detrimental gases, moisture and unfavorable weather conditions.

Another element of the car-carried apparatus comprises a suitable brake control device which has been conventionally illustrated by an electrically operated valve EPV. This brake control device EPV may take any one of various forms, that is, may apply the brakes by actuating the usual engineers brake valve in a manner so that the engineer cannot prevent its operation, may vent the brake pipe directly or may control a suitable bral-re applying device which vent-s the brake pipe to a predetermined extent only, and for convenience has been shown in a conventional manner.

in the car-carried circuit arrangement illustrated in Fig. 3 are provided two speed restricting devices such as shown in F 2, and for COHVCDlODCO like parts of the low speed. restricting devices are designatdby like reference characters 'ot the high speed restricting device with distinctive expouents L.

The speed restricting device for operating the high cam as shown in l ig ti ii; provided .u'ith additional distance cams which have not been shown inFig. 2. Two of these distance earns 65 and (Share adapted to operate normally open contacts 67 and 68, whereas the distance cam 69 is adapted to operate normaliyclosed contacts 70 for purposes more clearly described in the operation of the system. These contacts are operated by rollers engaging the periphery of the cams, as shown and need no i'urtner descrip- 'tion. The low cam speed restricting appara O peraton.

Normal cZco/r conditions of the car-carried appamtus.%Under normally clear traiiic conditions of the car-carried apparatus as would be the case it the car were passing through a clear block, the primary coil P oi the car element L is energized by a circuit beginning at the tern'iinal B of a suitable source of energy having its other terminal connected to a common return wire C, and including the contacts 55 of the high cam speed. restrictingapparatus the contacts 55 of the low cam speed i s icting apparatus and the brake control device EPV in series, the how oi current in this circuit causes an appreciable magneto-motive-l orce to be set up in the car element L for reasons hereimitter given. The speed distance contact 55 oi the low cam speed restricting device is normally shunted by the contacts 73, as shown. The control relay CR and the secondary coil S are connected in series and are normally energized through a circuit which may be traced as follows :beginning at the terminal B of a suitable source of energy, wire 78, front contact 79, of the control relay Cit, wires and 81, winding of the control relay CB, wire 82, secondary coil S liaclrto the common return wire C. The current flowing in this circuit and the secondary coil '8 is very small and does not materially change the magnetization ofthe car element, it being just suflicient to maintain the relay Cl;

energized. l' i ith this control relay CR energized the repeater relay RE is energized by a circuit readily traced .in the drawing. With the repeater relay RR energized a circuit may be traced for the high cam" start-' ing magnet HUS comprising wire 83,'lront contact 8% of the repeater relay RR, wire 8), winding 36 of the cam starting magnet HUS, I wire 86, stick contact 87 of said magnet, back to the common return wire C; and another and similar rircuit may be traced through the Winding 3G oi' the low cam starting magnet [JCS including the wires 88, 89 and 90 and the slick contact 87 of this low cam starting magnet LCS. Another circuit may be traced for energizing the winding 36 oi the low cam sarting magnet LCS as follows :beginning at the terminal B oi a suitable source of energy, wire 91, contact 70, wires 92 and 89, winding 36 of the cam starting magnet LCS, wire 90 and stick contact 87?, so that the low cam starting magnet LCS is energizedindependent of the circuit including the "front contact 84 of the repeater relay RR. 7

Passing through caution Z007c.Let us assume that a railway vehicle is moving from leftto right in the normal direction or" tral'lic as indicated by the arrow in Fig. 1 at a speed of, say, a little less than 60 miles per hour in the block H, when the second block ahead, namely the block J, is occupied by another train, it being assumed that the block I is unoccupied by another train, for otherwise the train would have already been restricted in the block l-l. l Vith the block J ahead occupied by another train the track relay 4: assumes its deenergized position thereby deenergizing the line relays 9 and ll a n d putting the coils 'Z, i and l of the track elements in an open circuit. [is the train in question enters the block l the car element 11 E comes into con'nrunucating relation with the track element T. Since, as heretofore explained, the car element L has its primary coil energized, a strong held or"- flux radiates trom the leg carrying this primary coil. .lhis nun ordinarily passes, to a large extent, through leakage paths back to the upper part of this leg, part of the flux of course passing through the secondary coil S.

As the car element L passes over the track elementv T the magnetic circuit including the core 62, is momentarily shunted, so to speak,

by the core of the track element T, so that a sudden increase in flux through the secondary coil S takes place. This sudden. increase of flux, it is belicvec, is partially due to a diversion of flux from leakage paths, as just explained, and is partially due to an increase in the total flux passing through the primary coil P. As the car elementli receeds from the track element T, the flux through the secondary coil S again changes back to normal, so that a rapid increase and then a decrease of flux through the secondary coil takes place. This rapid increase and decrease of flux through the secondary coil S, by well-known principles otinduction, causes a varying voltage to be induced in this secondary coil. S which. Voltao corresponds to a single cycle of alternating current electro-n'iotive-lorcc. The winding oi? the coil S-is connected to the control relay 1R in a manner, so that, the first wave of this cycle of: alternating current voltage opposes the voltage supplied by the battery having a tcrn'unal B which energizes the control relay CR, whereby the ciurrent flowing in the control relay is reduced to an extent to momentarily deenergiz-e this relay. l l ith the relay once deencrgized the front contact 79 of this relay GR is opened and its energizing circuit permanently interrupted, so that this relay remains deenergized until it is again picked up. by some other means. Deenergization of this relay 'Clt causes deenergization ot the repeater lay RR and consequently d-eenergization of the high cam starting magnet HGS. lVith the high cam starting magnet HUS deenergized the spring 33 moves the pinion 31. into engagementwith the gear 38 thereby causing rotation of the cam shaft After a slight amount of rotation of this shaft 39 the contacts 68 are closed, thereby again picking up the control relay CR. This control rclay CB again picks up the repeater relay HR which closes its from contact 8st but does not again energize the high cam starting magnet HOS because the stick contact 87. t this magnet is open.

As the vehicle proceeds through the b ock I the cam 46 is gradually rotated. thereby moving the floating lever 49in. direction to move the sector a7 clockwise. It the sgecd of the vehicle is not reduced in lilm'manncr so that the lower. end ot'the arm moves to the right to the ,same'extent that roller 50 moves to the left the contacts will be opened and the brakes applied, consequently the engineer must gradually reduce the speed of the train as restricted by the cam. l6 to avoid an automatic brake application. The cam 46 may be cutto restrict the saeed in any desired manner, the graph 16 in Fig. 1 illustrating the speed restriction indicted by the particular earn as shown. 7

As the train reaches the track element T this element being in its open circuited eiliective condition, the control relay GR having again been picked up, causes the transmis sion of a similar impulse thereby again deenergizing the control relay CR and in turn the repeater relay RE. The deenergization of the repeater relay RR, in this case, deenergizes the low cam starting magnet, because the contact operate-db the distance cam 69 of the high cam shaft is open. The control relay CE will now remain 'deenergizeduntil restored in a manner to be described later. With the low caininitiated by the track element T the speed of the train is restricted from the medium to suecessive lower speeds until finally the minimum speed 01 15 miles per hour reached, the low speed-distance contact being made cfiective by the opening or" contacts 73 after a short distance 0'! moven'ient of the train after the low'speed restricting mechanism Also. alter a short dis-.

has been initiated. tance of movement; of the train a'l .er the low speed restricting mechanism has been initiatcd the cam 71 completes a pick-up circuit for the control relay which may be traced as follows:-beginning at the terminal B of the battery, contacts 77, wires 9- and 81, winding of the control relay GR, wire 82, secondary coil S, hack to the common return wire C. The completion ofthis pick up circuit causes the control relay OR to again be picked up and maintained u b its stick circuit. i i

. back to the common return wire C, so that the high cam is again restored to its normal position by reason of the retaining gear sector 42 and the springs 43. 1

The low cam Continues to restrict the speed.

of the train as shown by the dot-and-dash line 17, (see Fig. As the low cam has reached a predetermined position the dis tance cam 74 completes a pick up circuit for the low cam starting magnet LCS which may be traeed toilowsz-beginning at the terininal B of the battery, wire 83, front contact 8 ot the repeater relay RR, wires 88 and 89, winding 86 of the low cam starting magnet LCS, wires 90 and 97, contact 7 5, back to the common return wire C.

In applying the apparatus described to a very short block it may well happen that the low cam reaches its ultimate position before the high cam reaches its ultimate position, and in order to restore the high cam at least as soon as the low cam is restored additional contacts 7 6 adapted to beclosed by the distance cam 74 have been provided. These contacts 7 6 are adapted topick up the high canr starting magnet by completing the following circuit:beginning at the terminal B of the battery, wire 83, front contact of the repeater relay (this relay beingenergized for reasons heretofore given), wire 85, winding 36 of the high cam starting magnet HOS, wires 86, 96 and 98, contacts 76, back to the common return wire'C. In the particular arrangement shown and described it is contemplated to effect restoration of the low cam a short distance of travel after this low cam has reached its minin'iuin speed position, as isi'ndicated by the dot-and-dash line 17 in Fig. 1. As shown in Fig. 1 a longer distance of travel of the train is required to operate the high cam to the position in which it restores itself (the distance from track element T to the vertical portion of solid line 16, Fig. 1) than the distance of travel required torestore the low cam (the distance from track element T to the vertical portion of dot-and-dash line 17). This Cllil GPSDCQ in the run-down distances may be obtained by using ditl'erent gear ratios for driving these two cams from the same shaft or the distance cams 71,72 and 74 may be shaped to obtain the desired result with the same gear ratios. It is thus apparent that the speed restriction is released at the end of the caution block by reason of the self restoring characteristics of speed restricting mechanism.

In the particular block I illustrated the restrictions enforced by the two speed restricting devices overlap each other as shown by curves 1 6 and 17 in Fig. 1. This is however not essential, tor-instance, in a short block they may be started 'at practically the sa-iiie point, the track elements T and T starting both cams which will both be restored when the low speed restricting mechnism reaches its ultimate position by the action of contacts 7 5 and 76 closed by the cam 74:. Also, the low speed 'estricting mechanism may be initiated at the entrance to a caution block by placing two track elements at such point spaced substantially the same as the elements T" and T. In other words the track elements T, T and T will be placed at points depending on the length of the block, the grade, the condition of the trackway, and the like, so that the train in each event will be brought to a predetermined low speed or to a stop before reaching theend of a caution block. Since the starting of the second or low cam depends on the conditioner the tirst or hi 'h cam, this high cam may be considered to a conditioning means determining the starting of the low cam even though this high cam accomplishes other and additional functions.

lV/ten passing aftough a clear bZ00]c.Let us assume now that the train in question is approaching the block l'from the left under clear traffic conditions ahead, that is, with thetrack relay 4 and the line relays 9 and 11 energized. Asthe'trai-n approaches the track element T and the car element L comes llltOCOIHlDUIilCtltillg relation with this track element no impulse is transmitted to the control relay OR to deenergize this re lay. Gne theory by which this failure of re sponse may be accounted for, isthat the passageojt a small number'o't' magnetic lines through the track element T causes a cur rentto flow in the coil'Zby induction, which coiliis now closed in a circuit of low resistance, thereby causing this current to setup a counter magneto-motive-torce which opposes aturther change of flux, all in accordance with the well-known principle of induction of alternating currents. In other Words, the coil 7 when closed in a circuit of low resistance acts as a bucking coil andjprevents the passage of flux-through the track element T,

so'that this track element does not have the characteristics of a piece ofmagnetic material, especially to. the car element as it passes thereby very quickly. Since Very little, if any, change of flux takes place through the secondary coilS insufiicient voltage is in duced in this coil to oppose the battery and deenergize the relay CR so that thisrelay GR is maintained energized and the car-carried apparatus remains unchanged in passing over the track element T.

The function of the car-carried and trackway apparatus when the car element L passes by the track elements T and 'l. with these track elements in their clear traiflc condition, as shown, is exactly the same as that which occurs when passing the track element T, so that: further description of the operation is unnecessary.

Having shown and described one specific embodiment of the present invention, it should be understood that the specific features shown and described have been chosen for the purpose of illustrating the nature of the invention rather that its scope, and it is desired to be understood that various changes, additions and modifications may be made to adapt the invention to the various i railway systems encountered in practice trackway, means governed by one said speed restricting devices and active only when it is in its normal condition for independently maintaining the other device in its inactive condition, and tralfic controlled means located at points along the trackway for transmitting control influences to said influence receiving'means under danger trafs fic conditions ahead.

2. An automatic train control system employing speed restricting devices of the cyclic type comprising, two separate cyclic speed restricting devices on a railway vehi ele, normally energized means for maintaining said devices in their normal inactive condition, influence receiving means for deenergizing said last mentioned means upon the reception of a control influence from the trackway, means governed by one of said speed restricting devices and effective only when it is in its normal condition to prevent the other speed restricting device from being initiated, whereby one of said devices is initiated upon the reception of the first influence from the trackway and the other device is initiated upon the reception of a second influence, and trackway means located along the trackway totra-nsmit influences to said influence receiving means.

3. An automatic train controlsystem employing speed restricting devices of the cyclic type comprising, two separate cyclic speed restricting devices on a railway vehicle, normaliy energized means for maintaining said devices in their normal inactive condition, influence receiving means for deenergizing said last mentioned means upon the reception of a control influence irom the trackway, means active if one of said devices is in its inactive condition for preventing the other device from being initiated upon the reception or" a control influence, means asso ciated with each of said devices for restoring itself to its normal condition effective when such device has reached its ultimate condition, and trackway .IDQLIILS located at successive points along the trackway to transmit control influences to said car-carried influence receiving means.

4:. Car-carried apparatus for automatic train control systems comprising, two separate speed. restricting devices of the type which it initiated are operated in accordance with the progress of the veh cle along the trackway and which enforce successive lower speed limits until theyreach an ultimate po-. Sll'lOl], means associated with one of said de vices for restoring itself when it has reached its ultimate position, and means associated with the other device for restoring both oi? said devices to their normal position effective when said other device reaches its ultimate position.

5. Gar-carried apparatus for automatic train control systems comprising, two dis- 'tinct speed restricting devices each including a permissive speed device normally held in its maximum speed position by a normally energized electro-responsive device energized through a stick circuit which if deenergized permitssaid device to gradually assume more restrictivepermissive speed positions, influ- 1 ence receiving means adapted to momentarily open both of said stick circuits upon the reception of a control influence from the track way, means for independently maintaining the stick circuit oi one of said electro-responsive devices intact effective it the other speed device is in its normal condition, and means for restoring said permissive speed devices to normal.

(i. Car-carried apparatus for automatic train control systems comprising, two distinct speed. restricting devices each including a permissive speed device normally held in its maximum speed position by a normally euergized electro-responsive device energized through a stick circuit which it deenergized permits said device to gradually assume more restrictive permissive speed positions, influence receiving means adapted to momentarily open both of said stick circuits upon the reception of a control influence from the trackway, means governed by one of said permissive speed devices and. active when this device is in its normal position to independwhensaid other permissive speed device has reached its ultimate position.

7. In an automatic train control system, the combination oi car-carried inductive 1ntluence receiving means adapted to receive momentary impulses from suitable trackway elements through an intervening air gap, a permissive speed device normally held in its inactive position which it initiated assumes '1 more restrictive speed. positions'in accordance with the progress of the vehicle, means initiated in response to the reception of two successive control influences spaced apart 2i time allowing the vehicle to travel a certain distance and traclrway devices for transmit ting inductive control influences to said carcarried receiving means spaced a corresponding distance apart along the trackway.

8. Car-carried apparatus for automatic train control systemscomprising, an influence receiving element having a primary er:- citing coil and a secondary coil thereon, a control relay connected to said secondary coil, whereby the control relay will momentarily respond when said ear element passes over an active track element comprising an inert mass of iron, and means including a driving connection from the wheels of the vehicle for reducing the speed which the vehicle may attain without incurring an automatic brake application when placed in its active condition and adapted to be initiated.

only by the reception of two successive control, influences by said control relay spaced apart atleast a time corresponding to the time necessary for the vehicle to travel predetermined distance along ,the trackway.

t Car-carried apparatus for automatic train control systems comprising, a permissivc speed device, an actual speed device, means for receiving momentary control in :tluonces from the traclrway inductively lhriiiugh an intervening air gap, and means for causing said permissive speed device to iutlict a more restrictive speed limit, said last mci'itioncd means being eliective only it one control influence is received a predetermined distance of movement of the vehicle before another influence is received from the trackway.

l0. Car-carried apparatus torvautomatic train control systemscomprising; a train control mechanism; and means for initiating said mechanism including a carcarried influence receiving device and a plurality of influence transmitting devices each of which when in its active condition is capable of transmitting a control influenceto said carcarried device through an intervening airgap, and including means effective only if one control influence is received more than a predetermined distance of travel of the vehicle before another control influence is received.

11. Car-carried apparatus for automatic train control systems comprising; a train control mechanism; and means for initiating said mechanism including a car-carried influence receiving device and a plurality of influence transmitting devices each of which when in its active condition is capable oi transn'iitting a control influence to saidcar-carried device through an intervcning air-gap, and including means effective only it one control. influence is received more than a predetermined distance of travel of the vehicle before another control influence is received provided the said another control influence is not received more than another predetermined distance ot travel after the first control influence is received.

12. In an automatic "train control system the combination of train control mechanism, influence communicating means partly on the vehicle and partly along the trackway for intermittently transmitting controlinlluences from the traclrway to the vehicle through an intervening air-gap, and means for initiating said train control mechanism eflective only it two control influences are transmitted during the time that the vehicle travels more than a certain fixed distance and travels less than another fixed distance. I

13. Car-carried apparatus for automatic train control systems comprising, normally energized and inactive train control mechanism, two circuits for energizing said mechanism, means for opening one of said circuits ei'iiective if a control influence isreceived and for opening the other circuit eti cct-ive only after the vehicle has traveled a predetermined distance after the reception of such control influences and thereafter a second control influence is received.

14-. Car-carried apparatus for automatic train control systems compr mg; normally inactive and normally energized train control mecl'ianism, two stick circuits for rendering said mechanism inactive; means for breaking one of these circuits upon the re ception of a. control influence trausn'iitted from the traclrway, and for breaking the other circuit upon the reception of a second control influence from' the trackway providing the car has traveled more than a predetermined distance since the reception of the previous control influence;

15. Car-carried apparatus for autou'iatic train control systems comprising; normally inactive and normally energized train control mechanism, two stick circuits for said mechanism means for breaking one of these circuits upon the reception of a control influence transmitted from the trackway, and

.1 spaced apart a time pernn,

for breaking the other circuit upon the reccption of a second control influence from the traclrway providing the car has traveled more than a predetermined distance since the reception ot the previous control influence and further providing the car has not traveled more than another predetermined distance since the reception of such previous control influence. v

1.6. Car-carried apparatus tor automatic train control systems comprising, train control mechanism, a normally energized stick relay, a conditioning device which when in its active condition permits said train control mechanism to be operated by dropping oi said stick relay and which is rendered active alter said stick re ay has been deenergized, influence receiving means for deenergizing said stick relay, means operated in accordance with the progress of the vehicle for picking up said stick relay, whereby said train control mechanism is operated it a second control influence is received and the two successive control influences are received ting the train to travel a predetermined distance.

17. Carcarried apparatus for automatic train control systems comprising, train control mechanism, a control relay, a conditioning device controlled. by said control relay train control systems ell'eetive only it the train has traveled a predetermined distance alter said control relay has been, operated and which conditioning device it e'llective permit-s said train control device to be operated by said control relay, and influence receiving means for operating said control relay in response to magnetic control influences transmitted by suitable trackway a 'iparatus,whereby said train control. mechanism is operated ii? two successive control influences are received spaced apart more than a predetermined distance of travel of the train.

18. Car-carried apparatus for automatic con'iprising, train control mechanism which it rendered active g radually restricts the speed of the vehicle -in accordance with. its progress along the track, a conditioning device, a control relay, influence receiving means responsive to a magnetic field ot a trackway device for ac tuating said control relay, said control relay it actuate-d rendering said conditioning means active after a time and said control relay it actuated while said conditioning means is active rendering said train control mechanism active.

In testin'iony whereof I hereby ailix my signature.

Pane n. canrnn. 

